Heat transfer fluid flow control device

ABSTRACT

A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit is described. The flow control device includes an inlet port fluidly communicable with a fluid source and first and second outlet ports, the first outlet port is fluidly communicable with a first device, and the second outlet port is fluidly communicable with a second device. The flow control device further includes an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

FIELD

This disclosure relates generally to a refrigeration system. More specifically, the disclosure relates to a system for controlling flow of heat transfer fluid in a heat transfer circuit of the refrigeration system.

BACKGROUND

A refrigeration system is generally used to control one or more environmental conditions such as, but not limited to, temperature and/or humidity of a refrigerated space. A refrigerated space is commonly used to store perishable items such as produce, frozen foods, and meat products. Generally, the refrigerated space includes a heat transfer circuit configured to control one or more environmental conditions (e.g., temperature, humidity, etc.) of a particular space (generally referred to as a “conditioned space,” a “refrigerated space,” or the like). The refrigeration system can include, without limitation, a compressor, a condenser, an expansion valve, an evaporator, and fans or blowers to control the heat exchange between the air inside the conditioned space and the ambient air outside of the conditioned space.

SUMMARY

This disclosure relates generally to a refrigeration system. More specifically, the disclosure relates to a system for controlling flow of heat transfer fluid in a heat transfer circuit of the refrigeration system.

In some embodiments, a flow control device in a heat transfer circuit can be used to control an operating mode of the refrigeration system. The flow control device can be a three-way flow control device to selectively direct flow of a heat transfer fluid from a compressor toward a condenser, an evaporator, or a combination thereof. In some embodiments, the flow control device can be referred to as a three-way valve.

In some embodiments, the heat transfer circuit can be operated in a cooling mode. In the cooling mode, the flow control device can be configured such that the heat transfer fluid is received from the compressor and directed toward the condenser.

In some embodiments, the heat transfer circuit can be operated in a heating/defrost mode. In the heating/defrost mode, the flow control device can be configured such that the heat transfer fluid is received from the compressor and directed toward the evaporator.

In some embodiments, the heat transfer circuit can be operated in a modulating mode. In the modulating mode, the flow control device can be configured such that a portion of the heat transfer fluid received from the compressor is directed toward the evaporator and a portion of the heat transfer fluid received from the compressor is directed toward the condenser.

In some embodiments, the flow control device includes a stepper motor and a spool. The stepper motor can be configured to modify a location of the spool such that a portion of the spool is in contact with a condenser side seat or an evaporator side seat. In some embodiments, the contact between the spool and the condenser side seat or the evaporator side seat can determine in which mode the heat transfer circuit operates.

In some embodiments, the flow control device can be used in an application other than a heat transfer circuit. In such embodiments, the flow control device can be used in various environments in which fluid from a single source is to have a controlled output to a plurality of devices.

A flow control device for directing flow of a fluid in a fluid circuit is described. The flow control device includes an inlet port fluidly communicable with a fluid source and first and second outlet ports, the first outlet port is fluidly communicable with a first device, and the second outlet port is fluidly communicable with a second device. The flow control device further includes an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit is described. The flow control device includes an inlet port fluidly communicable with a discharge port of a compressor in a heat transfer circuit and first and second outlet ports, the first outlet port is fluidly communicable with an evaporator in the heat transfer circuit, and the second outlet port is fluidly communicable with a condenser in the heat transfer circuit. The flow control device further includes a stepper motor; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

A refrigeration circuit is described. The refrigeration circuit includes a compressor, a flow control device, a condenser, and an evaporator fluidly connected. The flow control device includes an inlet port fluidly connected to a discharge port of the compressor and first and second outlet ports, the first outlet port is fluidly connectable to the evaporator, and the second outlet port is fluidly connectable to the condenser. The flow control device further includes a stepper motor; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

A transport refrigeration system (TRS) is described. The TRS includes a refrigeration circuit, including a compressor, a flow control device, a condenser, and an evaporator fluidly connected. The flow control device includes an inlet port fluidly connected to a discharge port of the compressor and first and second outlet ports, the first outlet port is fluidly connectable to the evaporator, and the second outlet port is fluidly connectable to the condenser. The flow control device further includes a stepper motor; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

A flow control device for directing flow of a fluid in a fluid circuit is described. The flow control device includes an inlet port fluidly communicable with a fluid source and first and second outlet ports, the first outlet port is fluidly communicable with a first device, and the second outlet port is fluidly communicable with a second device. The flow control device further includes a stepper motor; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit is described. The flow control device includes an inlet port fluidly communicable with a discharge port of a compressor in a heat transfer circuit and first and second outlet ports, the first outlet port is fluidly communicable with an evaporator in the heat transfer circuit, and the second outlet port is fluidly communicable with a condenser in the heat transfer circuit. The flow control device further includes an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

A refrigeration circuit is described. The refrigeration circuit includes a compressor, a flow control device, a condenser, and an evaporator fluidly connected. The flow control device includes an inlet port fluidly connected to a discharge port of the compressor and first and second outlet ports, the first outlet port is fluidly connectable to the evaporator, and the second outlet port is fluidly connectable to the condenser. The flow control device further includes an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

A transport refrigeration system (TRS) is described. The TRS includes a refrigeration circuit, including a compressor, a flow control device, a condenser, and an evaporator fluidly connected. The flow control device includes an inlet port fluidly connected to a discharge port of the compressor and first and second outlet ports, the first outlet port is fluidly connectable to the evaporator, and the second outlet port is fluidly connectable to the condenser. The flow control device further includes an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

A method for controlling an operating mode of a refrigeration circuit is also described. The refrigeration circuit includes a compressor, a flow control device, a condenser, and an evaporator fluidly connected. The flow control device includes an inlet port fluidly connected to a discharge port of the compressor, first and second outlet ports, the first outlet port being fluidly connectable to the evaporator, and the second outlet port being fluidly connectable to the condenser, a stepper motor, a first seat disposed between the inlet port and the first outlet port, a second seat disposed between the inlet port and the second outlet port, and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats. The method includes receiving a heat transfer fluid from the compressor at the inlet port of the flow control device; and translating the single spool between the first and second seats to direct the heat transfer fluid to one of the first and second outlet ports. In a cooling mode, the method includes translating the single spool to be sealingly engaged with the first seat such that heat transfer fluid is directed to the second outlet port. In a heating/defrost mode, the method includes translating the single spool to be sealingly engaged with the second seat such that the heat transfer fluid is directed to the first outlet port.

BRIEF DESCRIPTION OF THE DRAWINGS

References are made to the accompanying drawings that form a part of this disclosure, and which illustrate embodiments in which the systems and methods described in this specification can be practiced.

FIG. 1A illustrates a heat transfer circuit configured in a cooling mode, according to some embodiments.

FIG. 1B illustrates a heat transfer circuit configured in a heating/defrost mode, according to some embodiments.

FIG. 2A illustrates a flow control device in a first mode, according to some embodiments.

FIG. 2B illustrates the flow control device illustrated in FIG. 2A in a second mode, according to some embodiments.

FIG. 3 illustrates a flow control device in a third mode, according to other embodiments.

FIG. 4 illustrates a side view of a refrigerated transport unit, according to some embodiments.

Like reference numbers represent like parts throughout.

DETAILED DESCRIPTION

This disclosure relates generally to a refrigeration system. More specifically, the disclosure relates to a system for controlling flow of heat transfer fluid in a heat transfer circuit of the refrigeration system.

In some embodiments, the flow control system can be used in any refrigeration system configured to be switchable between a heat/defrost mode and a cooling mode. In some embodiments, the flow control system can be used in a transport refrigeration system (TRS). TRS is generally used to control one or more environmental conditions such as, but not limited to, temperature, humidity, and/or air quality of a transport unit. Examples of transport units include, but are not limited to, a container on a flat car, an intermodal container, a truck, a boxcar, or other similar transport units. A refrigerated transport unit can be used to transport perishable items such as, but not limited to, produce, frozen foods, and meat products.

As disclosed in this specification, a TRS can include a transport refrigeration unit (TRU) which is attached to a transport unit to control one or more environmental conditions (e.g., temperature, humidity, air quality, etc.) of an interior space of the refrigerated transport unit. The TRU can include, without limitation, a compressor, a condenser, an expansion valve, an evaporator, and one or more fans or blowers to control the heat exchange between the air within the interior space and the ambient air outside of the refrigerated transport unit.

A “transport unit” includes, for example, a container on a flat car, an intermodal container, truck, a boxcar, or other similar transport unit.

A “transport refrigeration system” (TRS) includes, for example, a refrigeration system for controlling the refrigeration of an interior space of a refrigerated transport unit. The TRS may be a vapor-compressor type refrigeration system, a thermal accumulator type system, or any other suitable refrigeration system that can use heat transfer fluid, cold plate technology, or the like.

A “refrigerated transport unit” includes, for example, a transport unit having a TRS.

Embodiments of this disclosure may be used in any suitable environmentally controlled transport apparatus, such as, but not limited to, an over the road truck cabin, an HVAC system for a bus, a hydrogen-powered fuel cell, a heat-powered refrigeration system where pressurized fuel is used as a heat source, or the like.

FIGS. 1A-1B illustrate heat transfer circuits 100A-100B configured in a cooling mode (100A of FIG. 1A) and a heating/defrost mode (100B of FIG. 1B), according to some embodiments. The heat transfer circuits 100A-100B generally include a compressor 5, a condenser 10, an expansion device 30, an evaporator 40, and a flow control device 85. The compressor 5 includes a discharge port 50 and a suction port 55. The components of the heat transfer circuits 100A-100B are connected in fluid communication. It is to be appreciated that the heat transfer circuits 100A 100B can include one or more additional components. Examples of additional components include, but are not limited to, a receiver tank, a dryer, a suction-liquid heat exchanger, an economizer, or the like.

The discharge port 50 of the compressor 5 is connected to an inlet port 300 of a flow control device 85. The flow control device 85 can, for example, be a three-way valve in some embodiments. The flow control device 85 is described in further detail in accordance with FIGS. 2A-2B below. In some embodiments, the flow control device 85 can also be connected to the suction side (e.g., the low-pressure side) of the compressor 5.

In some embodiments, the heat transfer circuits 100A-100B can include a hot-gas bypass (not shown). The hot-gas bypass can be configured to provide high-pressure heat transfer fluid directly to a relatively lower pressure side of the heat transfer circuit 100A when in the cooling mode (e.g., heat transfer circuit 100A of FIG. 1A). That is, the hot-gas bypass can divert high-pressure heat transfer fluid such that it is not directed to the condenser 10, but instead is directed to the evaporator 40 when in the cooling mode (e.g., heat transfer circuit 100A of FIG. 1A).

A selected configuration of flow control device 85 can be used to determine an operating mode for the heat transfer circuit (e.g., a cooling mode as shown in FIG. 1A or a heating/defrost mode as shown in FIG. 1B). The flow control device 85 can be controlled by a controller (not shown) to select the operating mode. The flow control device 85 has a plurality of outlet ports 305, 310. The flow control device 85 can selectively output heat transfer fluid to the outlet ports 305, 310 to control whether the heat transfer circuits 100A-100B are operating in the cooling mode (e.g., heat transfer circuit 100A of FIG. 1A) or the heating/defrost mode (e.g., heat transfer circuit 100B of FIG. 1B).

In the cooling mode (heat transfer circuit 100A as shown in FIG. 1A), high-pressure gas heat transfer fluid from the compressor 5 is directed from the outlet port 305 of the flow control device 85 to the condenser 10. In the heating/defrost mode (heat transfer circuit 100B as shown in FIG. 1B), the high-pressure gas heat transfer fluid is directed from the outlet port 310 of the flow control device 85 to the evaporator 40. The heating/defrost and cooling modes operate according to principles known in the art unless explicitly described to the contrary.

In some embodiments, the flow control device 85 can be configured such that a portion of the heat transfer fluid is output from the outlet port 305 and a portion of the heat transfer fluid is output from the outlet port 310. In some embodiments, this can be referred to as a modulated cooling mode, modulated heating/defrost mode, or the like.

It is to be appreciated that the flow control device 85 can be operated similarly in a fluid circuit other than a heat transfer circuit with a fluid other than a heat transfer fluid.

FIGS. 2A-2B illustrate the flow control device 85 in a first mode (FIG. 2A) and in a second mode (FIG. 2B), according to some embodiments.

FIG. 2A illustrates the flow control device 85 in a first mode, according to some embodiments. In the illustrated embodiment, the first mode corresponds to a cooling mode (e.g., the cooling mode as shown in the heat transfer circuit 100A of FIG. 1A) when the flow control device 85 is used in a heat transfer circuit. It is to be appreciated that the first mode may be referred to by a different name if the flow control device 85 is used in a fluid flow circuit other than a heat transfer circuit. The embodiment illustrated in FIG. 2A will be described in accordance with the heat transfer circuit of FIGS. 1A 1B. In embodiments in which the flow control device 85 is included in a fluid flow circuit other than a heat transfer circuit the connections between inlet and outlet ports, fluid described, etc., may be different, but similar functionality is intended to be within the scope of this disclosure.

The flow control device 85 includes an inlet port 300 and outlet ports 305, 310. The inlet port 305 is connected in fluid communication with the compressor 5 (FIGS. 1A-1B) such that high-pressure gas heat transfer fluid can be received from the compressor 5. The outlet port 305 is connected in fluid communication with the condenser 10 (FIGS. 1A-1B). The outlet port 310 is connected in fluid communication with the evaporator 40 (FIGS. 1A 1B). In some embodiments, the inlet port 300 can be disposed on a first side of a longitudinal axis of a shaft 210A of a sealing member 210 and the outlet ports 305, 310 can be on a second side, opposite the first side, of the longitudinal axis of the shaft 210A of the sealing member 210. When in the first mode, the arrow F illustrates a flow of fluid through the flow control device 85. In some embodiments, longitudinal axes through outlet ports 305, 310 are disposed on opposite sides of a longitudinal axis through inlet port 300.

The flow control device 85 includes an actuator 205, the sealing member 210, an evaporator side seat 215, and a condenser side seat 220.

The actuator 205 is configured to move the sealing member 210 between the evaporator side seat 215 and the condenser side seat 220 (e.g., translating in a left-right/right-left movement according to FIG. 2A). The actuator 205 can be, for example, controlled by a controller (not shown) for a heat transfer circuit (e.g., heat transfer circuits 100A-100B of FIGS. 1A 1B) in order to selectively switch between the first mode (e.g., cooling mode) and the second mode (e.g., heating/defrost mode as shown and described in further detail in accordance with FIG. 2B below).

In general, the actuator 205 can be a variety of devices capable of moving the sealing member 210 between the evaporator side seat 215 and the condenser side seat 220. In some embodiments, the actuator 205 can be a stepper motor. In some embodiments, the actuator 205 can be a solenoid. The actuator 205 can be selected based upon various design considerations. For example, when the actuator 205 is a stepper motor, the number of steps it takes for the stepper motor to translate the sealing member 210 from the evaporator side seat 215 to the condenser side seat 220 may be selected to control a duration of time for the sealing member 210 to translate from the evaporate side seat 215 to the condenser side seat 220. In some embodiments, the number of steps may be selected such that the translation occurs quickly so that the modes are changed without a prolonged period in which heat transfer fluid can flow along both outlets 305, 310, but without causing too rapid of an increase in pressure which can cause premature breakdown of components within the heat transfer circuit. For example, in some embodiments, the number of steps can be about 1,000. It is to be appreciated that this number is exemplary and can be modified according to the principles described in this specification.

The sealing member 210 includes the shaft 210A connected to the actuator 205 and a sealing surface 210B configured to mate with either the evaporator side seat 215 or the condenser side seat 220 to control a flow direction of the heat transfer fluid (e.g., flow enabled through the outlet port 305, flow enabled through the outlet port 310, or a combination of flow enabled through both outlet ports 305, 310) depending on a location of the sealing surface 210B of the sealing member 210. It is to be appreciated that the sealing member 210 can have alternative configurations or be referred to differently so long as the sealing member 210 includes a sealing surface 210B movable between the evaporator side seat 215 and the condenser side seat 220. The sealing surface 210B includes two sealing surfaces in order to form a sealing bond with either the evaporator side seat 215 or the condenser side seat 220 depending on the location of the sealing member 210. The sealing surface 210B can be any configuration that when in contact with either the evaporator side seat 215 or the condenser side seat 220 forms a seal preventing fluid flow in the direction of the seal (e.g., preventing flow through either outlet 305 or 310). In some embodiments, the evaporator side seat 215 and the condenser side seat 220 can be generally annular members (e.g., an annular gasket or the like) and the sealing surface 210B can be a generally annular member. The sealing member 210B can, for example, be a spool. Spools and corresponding seats function according to principles known in the art.

FIG. 2B illustrates flow control device 85 in a second mode, according to some embodiments. In the illustrated embodiment, the second mode corresponds to a heating/defrost mode (e.g., the heating/defrost mode as shown in the heat transfer circuit 100B of FIG. 1B). Aspects of FIG. 2B are the same as or similar to aspects of FIG. 2A. Accordingly, for simplicity of this specification, aspects which are the same and were previously described will not be described in additional detail. In FIG. 2B, the sealing surface 210B of the sealing member 210 is in contact with the condenser side seat 220. Accordingly, flow of heat transfer fluid from the compressor 5 (FIGS. 1A 1B) is prevented from flowing through the outlet port 305 and is instead diverted through outlet port 305 toward the evaporator 40. When in the first mode, the arrow F illustrates a flow of fluid through the flow control device 85.

FIG. 3 illustrates flow control device 85 in a third mode, according to other embodiments. In the illustrated embodiment, the third mode generally corresponds to a modulated cooling mode. Aspects of FIG. 3 are the same as or similar to aspects of FIGS. 2A-2B. Accordingly, for simplicity of this specification, aspects which are the same and were previously described will not be described in additional detail. In FIG. 3, the sealing surface 210B of the sealing member 210 is in a position slightly translated away from the evaporator side seat 215. Accordingly, flow of heat transfer fluid from the compressor 5 (FIGS. 1A-1B) is generally diverted along flow path F toward the outlet 305. A portion of the heat transfer fluid from the compressor 5 also flows along flow path F′ through outlet 310. In the illustrated embodiment, the shaft 210A extends from the actuator 205 through the sealing surface 210B and is supported in a portion 330 of the flow control device 85. In some embodiments, the illustrated configuration may, for example, provide additional structural integrity to the sealing member 210 such that a sealing connection between the sealing surface 210B and the evaporator side seat 215 or condenser side seat 220 is maintained even when the fluid is under a relatively high pressure. In some embodiments, the additional structural integrity can increase reliability of the flow control device 85.

FIG. 4 illustrates a side view of a transport refrigeration system (TRS) 400 for a transport unit 425, according to some embodiments. The heat transfer circuits described above (e.g., heat transfer circuits 100A-100B of FIG. 1) can be implemented, for example, in the TRS 400. The illustrated transport unit 425 is a trailer-type transport unit. Embodiments as described in this specification can be used with other types of transport units. For example, the transport unit 425 can represent a container (e.g., a container on a flat car, an intermodal container, etc.), a truck, a boxcar, or other similar type of refrigerated transport unit including an environmentally controlled interior space.

The TRS 400 is configured to control one or more environmental conditions such as, but not limited to, temperature, humidity, and/or air quality of an interior space 450 of the transport unit 425. In some embodiments, the interior space 450 can alternatively be referred to as the conditioned space 450, the cargo space 450, the environmentally controlled space 450, or the like. In particular, the TRS 400 is configured to transfer heat between the air inside the interior space 450 and the ambient air outside of the transport unit 425.

The interior space 450 can include one or more partitions or internal walls (not shown) for at least partially dividing the interior space 450 into a plurality of zones or compartments, according to some embodiments. It is to be appreciated that the interior space 450 may be divided into any number of zones and in any configuration that is suitable for refrigeration of the different zones. In some examples, each of the zones can have a set point temperature that is the same or different from one another.

The TRS 400 includes a transport refrigeration unit (TRU) 410. The TRU 410 is provided on a front wall 430 of the transport unit 425. The TRU 410 can include an internal combustion engine (not shown) that provides mechanical power directly to a component (e.g., a compressor, etc.) of the TRS 400. In some embodiments, the engine of the TRU 410 can provide power directly to an alternator (not shown), which can be used to power the component. In such embodiments, the TRU 410 can include an electric drive motor that provides mechanical power directly to the component (e.g., a compressor, etc.) of the TRS 400.

The TRU 410 includes a programmable TRS Controller 435 that includes a single integrated control unit 440. It will be appreciated that in other embodiments, the TRS Controller 435 may include a distributed network of TRS control elements (not shown). The number of distributed control elements in a given network can depend upon the particular application of the principles described in this specification. The TRS Controller 435 can include a processor, a memory, a clock, and an input/output (I/O) interface (not shown). The TRS Controller 435 can include fewer or additional components.

The TRU 410 also includes a closed heat transfer circuit (not shown in FIG. 4). Generally, the TRS Controller 435 is configured to control a heat transfer cycle (e.g., controlling the closed heat transfer circuit of the TRU 410) of the TRS 400. In one example, the TRS Controller 435 controls the heat transfer cycle of the TRS 400 to obtain various operating conditions (e.g., temperature, humidity, air quality, etc.) of the interior space 450.

The TRS 400 includes an internal combustion engine (not shown), according to some embodiments. In some embodiments, the internal combustion engine can generally include a cooling system (e.g., water or liquid coolant system), an oil lubrication system, and an electrical system. An air filtration system can filter air directed into a combustion chamber of the internal combustion engine. In some embodiments, the internal combustion engine is not specifically configured for the TRS 400, but can be a non-industrial internal combustion engine, such as an automotive internal combustion engine.

Aspects:

It is to be noted that any one of aspects 1-8 can be combined with any one of aspects 9-16, 17-24, 25-32, 33-40, 41-42, 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 9-16 can be combined with any one of aspects 17-24, 25-32, 33-40, 41-42, 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 17-24 can be combined with any one of aspect 25-32, 33-40, 41-42, 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 25-32 can be combined with any one of aspects 33-40, 41-42, 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 33-40 can be combined with any one of aspects 41-42, 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 41-42 can be combined with any one of aspects 43-44, 45-46, 47-48, and/or 49-50. Any one of aspects 43-44 can be combined with any one of aspects 45-46, 47-48, and/or 49-50. Any one of aspects 45-46 can be combined with any one of aspects 47-48 and/or 49-50. Any one of aspects 47-48 can be combined with any one of aspects 49-50.

Aspect 1. A flow control device for directing flow of a fluid in a fluid circuit, the flow control device comprising:

an inlet port fluidly communicable with a fluid source;

first and second outlet ports, wherein:

-   -   the first outlet port is fluidly communicable with a first         device, and     -   the second outlet port is fluidly communicable with a second         device;

an actuator;

a first seat disposed between the inlet port and the first outlet port;

a second seat disposed between the inlet port and the second outlet port; and

a single sealing member translatable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

Aspect 2. The flow control device according to aspect 1, wherein the sealing member includes a shaft and a sealing area, the sealing area configured to be sealingly engageable with the first and second seats.

Aspect 3. The flow control device according to aspect 2, wherein when the sealing member is in a first configuration, the sealing area is in sealing engagement with the first seat such that the inlet port is fluidly communicable with the second outlet port and the first outlet port is sealed from the inlet port.

Aspect 4. The flow control device according to any one of aspects 2-3, wherein when the sealing member is in a second configuration, the sealing area is in sealing engagement with the second seat such that the inlet port is fluidly communicable with the first outlet port and the second outlet port is sealed from the inlet port.

Aspect 5. The flow control device according to any one of aspects 2-4, wherein when the sealing member is in a third configuration, the sealing surface is disposed between the first and second seats such that the inlet port is in fluid communication with the first outlet port and the second outlet port.

Aspect 6. The flow control device according to any one of aspects 1-5, wherein the sealing member includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.

Aspect 7. The flow control device according to any one of aspects 1-6, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.

Aspect 8. The flow control device according to any one of aspects 1-7, wherein the first and second seats are annular and the sealing member is annular.

Aspect 9. A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit, the flow control device comprising:

an inlet port fluidly communicable with a discharge port of a compressor in a heat transfer circuit;

first and second outlet ports, wherein:

-   -   the first outlet port is fluidly communicable with an evaporator         in the heat transfer circuit, and     -   the second outlet port is fluidly communicable with a condenser         in the heat transfer circuit;

a stepper motor;

a first seat disposed between the inlet port and the first outlet port;

a second seat disposed between the inlet port and the second outlet port; and

a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

Aspect 10. The flow control device according to aspect 9, wherein the spool includes a shaft and a sealing area, the sealing area configured to be sealingly engageable with the first and second seats.

Aspect 11. The flow control device according to any one of aspects 9-10, wherein when the spool is in a first configuration, the spool is in sealing engagement with the first seat such that the inlet port is fluidly communicable with the second outlet port and the first outlet port is sealed from the inlet port.

Aspect 12. The flow control device according to any one of aspects 9-11, wherein when the spool is in a second configuration, the spool is in sealing engagement with the second seat such that the inlet port is fluidly communicable with the first outlet port and the second outlet port is sealed from the inlet port.

Aspect 13. The flow control device according to any one of aspects 9-12, wherein when the spool is in a third configuration, the spool is disposed between the first and second seats such that the inlet port is in fluid communication with the first outlet port and the second outlet port.

Aspect 14. The flow control device according to any one of aspects 9-13, wherein the spool includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.

Aspect 15. The flow control device according to any one of aspects 9-14, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.

Aspect 16. The flow control device according to any one of aspects 9-15, wherein the first and second seats are annular and the spool is annular.

Aspect 17. A refrigeration circuit, comprising:

a compressor, a flow control device, a condenser, and an evaporator fluidly connected,

wherein the flow control device includes:

-   -   an inlet port fluidly connected to a discharge port of the         compressor;     -   first and second outlet ports, wherein:         -   the first outlet port is fluidly connectable to the             evaporator, and         -   the second outlet port is fluidly connectable to the             condenser;     -   a stepper motor;     -   a first seat disposed between the inlet port and the first         outlet port;     -   a second seat disposed between the inlet port and the second         outlet port; and     -   a single spool movable by the stepper motor, the spool         configured to be sealingly engageable with the first and second         seats.

Aspect 18. The refrigeration circuit according to aspect 17, wherein a location of the spool corresponds to an operating mode of the refrigeration circuit.

Aspect 19. The refrigeration circuit according to any one of aspects 17-18, wherein in a heating/defrost mode, the flow control device is configured to direct fluid flow from the first outlet port.

Aspect 20. The refrigeration circuit according to any one of aspects 17-19, wherein in a cooling mode, the flow control device is configured to direct fluid flow from the second outlet port.

Aspect 21. The refrigeration circuit according to any one of aspects 17-20, wherein in a modulating mode, the flow control device is configured to direct a portion of fluid flow from the first outlet and a portion of the fluid flow from the second outlet.

Aspect 22. The refrigeration circuit according to any one of aspects 17-21, wherein the spool includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.

Aspect 23. The refrigeration circuit according to any one of aspects 17-22, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.

Aspect 24. The refrigeration circuit according to any one of aspects 17-23, wherein the first and second seats are annular and the spool is annular.

Aspect 25. A transport refrigeration system, comprising:

-   -   a refrigeration circuit, including:         -   a compressor, a flow control device, a condenser, and an             evaporator fluidly connected,     -   wherein the flow control device includes:         -   an inlet port fluidly connected to a discharge port of the             compressor;         -   first and second outlet ports, wherein:             -   the first outlet port is fluidly connectable to the                 evaporator, and             -   the second outlet port is fluidly connectable to the                 condenser;         -   a stepper motor;         -   a first seat disposed between the inlet port and the first             outlet port;         -   a second seat disposed between the inlet port and the second             outlet port; and         -   a single spool movable by the stepper motor, the spool             configured to be sealingly engageable with the first and             second seats.

Aspect 26. The transport refrigeration system according to aspect 25, wherein a location of the spool corresponds to an operating mode of the transport refrigeration system.

Aspect 27. The transport refrigeration system according to any one of aspects 25-26, wherein in a heating/defrost mode, the flow control device is configured to direct fluid flow from the first outlet port.

Aspect 28. The transport refrigeration system according to any one of aspects 25-27, wherein in a cooling mode, the flow control device is configured to direct fluid flow from the second outlet port.

Aspect 29. The transport refrigeration system according to any one of aspects 25-28, wherein in a modulating mode, the flow control device is configured to direct a portion of fluid flow from the first outlet and a portion of the fluid flow from the second outlet.

Aspect 30. The transport refrigeration system according to any one of aspects 25-29, wherein the spool includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.

Aspect 31. The transport refrigeration system according to any one of aspects 25-30, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.

Aspect 32. The transport refrigeration system according to any one of aspects 25-31, wherein the first and second seats are annular and the spool is annular.

Aspect 33. A flow control device for directing flow of a fluid in a fluid circuit, the flow control device comprising:

an inlet port fluidly communicable with a fluid source;

first and second outlet ports, wherein:

-   -   the first outlet port is fluidly communicable with a first         device, and     -   the second outlet port is fluidly communicable with a second         device;

a stepper motor;

a first seat disposed between the inlet port and the first outlet port;

a second seat disposed between the inlet port and the second outlet port; and

a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats.

Aspect 34. The flow control device according to aspect 33, wherein the spool includes a shaft and a sealing area, the sealing area configured to be sealingly engageable with the first and second seats.

Aspect 35. The flow control device according to any one of aspects 33-34, wherein when the spool is in a first configuration, the spool is in sealing engagement with the first seat such that the inlet port is fluidly communicable with the second outlet port and the first outlet port is sealed from the inlet port.

Aspect 36. The flow control device according to any one of aspects 33-35, wherein when the spool is in a second configuration, the spool is in sealing engagement with the second seat such that the inlet port is fluidly communicable with the first outlet port and the second outlet port is sealed from the inlet port.

Aspect 37. The flow control device according to any one of aspects 33-36, wherein when the spool is in a third configuration, the spool is disposed between the first and second seats such that the inlet port is in fluid communication with the first outlet port and the second outlet port.

Aspect 38. The flow control device according to any one of aspects 33-37, wherein the spool includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.

Aspect 39. The flow control device according to any one of aspects 33-38, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.

Aspect 40. The flow control device according to any one of aspects 33-39, wherein the first and second seats are annular and the spool is annular.

Aspect 41. A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit, the flow control device comprising:

an inlet port fluidly communicable with a discharge port of a compressor in a heat transfer circuit;

first and second outlet ports, wherein:

-   -   the first outlet port is fluidly communicable with an evaporator         in the heat transfer circuit, and     -   the second outlet port is fluidly communicable with a condenser         in the heat transfer circuit;

an actuator;

a first seat disposed between the inlet port and the first outlet port;

a second seat disposed between the inlet port and the second outlet port; and

a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.

Aspect 42. The flow control device according to aspect 41, wherein the actuator is a stepper motor and the sealing member is a spool.

Aspect 43. A refrigeration circuit, comprising:

a compressor, a flow control device, a condenser, and an evaporator fluidly connected,

wherein the flow control device includes:

-   -   an inlet port fluidly connected to a discharge port of the         compressor;     -   first and second outlet ports, wherein:         -   the first outlet port is fluidly connectable to the             evaporator, and         -   the second outlet port is fluidly connectable to the             condenser;     -   an actuator;     -   a first seat disposed between the inlet port and the first         outlet port;     -   a second seat disposed between the inlet port and the second         outlet port; and     -   a single spool movable by the stepper motor, the spool         configured to be sealingly engageable with the first and second         seats.

Aspect 44. The refrigeration circuit according to aspect 43, wherein the actuator is a stepper motor and the sealing member is a spool.

Aspect 45. A transport refrigeration system, comprising:

-   -   a refrigeration circuit, including:         -   a compressor, a flow control device, a condenser, and an             evaporator fluidly connected,     -   wherein the flow control device includes:         -   an inlet port fluidly connected to a discharge port of the             compressor;         -   first and second outlet ports, wherein:             -   the first outlet port is fluidly connectable to the                 evaporator, and             -   the second outlet port is fluidly connectable to the                 condenser;         -   an actuator;         -   a first seat disposed between the inlet port and the first             outlet port;         -   a second seat disposed between the inlet port and the second             outlet port; and     -   a single sealing member movable by the actuator, the sealing         member configured to be sealingly engageable with the first and         second seats.

Aspect 46. The transport refrigeration system according to aspect 45, wherein the actuator is a stepper motor and the sealing member is a spool.

Aspect 47. A method for controlling an operating mode of a refrigeration circuit, the refrigeration circuit including a compressor, a flow control device, a condenser, and an evaporator fluidly connected, wherein the flow control device includes an inlet port fluidly connected to a discharge port of the compressor, first and second outlet ports, the first outlet port being fluidly connectable to the evaporator, and the second outlet port being fluidly connectable to the condenser, a stepper motor, a first seat disposed between the inlet port and the first outlet port, a second seat disposed between the inlet port and the second outlet port, and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats, the method comprising:

receiving a heat transfer fluid from the compressor at the inlet port of the flow control device; and

directing the heat transfer fluid to one of the first and second outlet ports, wherein when the first outlet port receives the heat transfer fluid the refrigeration circuit is in a heating/defrost mode, and when the second outlet port receives the heat transfer fluid the refrigeration circuit is in a cooling mode.

Aspect 48. The method according to aspect 47, further comprising directing the heat transfer fluid to both the first and second outlet ports, wherein when both the first and second outlet ports receive the heat transfer fluid the refrigeration circuit is in a modulating mode.

Aspect 49. A method for controlling an operating mode of a refrigeration circuit, the refrigeration circuit including a compressor, a flow control device, a condenser, and an evaporator fluidly connected, wherein the flow control device includes an inlet port fluidly connected to a discharge port of the compressor, first and second outlet ports, the first outlet port being fluidly connectable to the evaporator, and the second outlet port being fluidly connectable to the condenser, a stepper motor, a first seat disposed between the inlet port and the first outlet port, a second seat disposed between the inlet port and the second outlet port, and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats, the method comprising:

receiving a heat transfer fluid from the compressor at the inlet port of the flow control device; and

translating the single spool between the first and second seats to direct the heat transfer fluid to one of the first and second outlet ports, wherein:

-   -   in a cooling mode, translating the single spool to be sealingly         engaged with the first seat such that heat transfer fluid is         directed to the second outlet port, and     -   in a heating/defrost mode, translating the single spool to be         sealingly engaged with the second seat such that the heat         transfer fluid is directed to the first outlet port.

Aspect 50. The method according to claim 19, wherein in a modulating mode, translating the single spool to an intermediate location between the first and second seats for directing a portion of the heat transfer fluid to the first outlet port and for directing another portion of the heat transfer fluid to the second outlet port.

The terminology used in this specification is intended to describe particular embodiments and is not intended to be limiting. The terms “a,” “an,” and “the” include the plural forms as well, unless clearly indicated otherwise. The terms “comprises” and/or “comprising,” when used in this specification, indicate the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and/or components.

With regard to the preceding description, it is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size, and arrangement of parts without departing from the scope of the present disclosure. The word “embodiment” as used within this specification may, but does not necessarily, refer to the same embodiment. This specification and the embodiments described are exemplary only. Other and further embodiments may be devised without departing from the basic scope thereof, with the true scope and spirit of the disclosure being indicated by the claims that follow. 

What is claimed is:
 1. A flow control device for directing flow of a heat transfer fluid in a heat transfer circuit, the flow control device comprising: an inlet port fluidly communicable with a discharge port of a compressor in a heat transfer circuit; first and second outlet ports, wherein: the first outlet port is fluidly communicable with an evaporator in the heat transfer circuit, and the second outlet port is fluidly communicable with a condenser in the heat transfer circuit; an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member translatable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.
 2. The flow control device according to claim 1, wherein the sealing member includes a shaft and a sealing area, the sealing area configured to be sealingly engageable with the first and second seats.
 3. The flow control device according to claim 2, wherein when the sealing member is in a first configuration, the sealing area is in sealing engagement with the first seat such that the inlet port is fluidly communicable with the second outlet port and the first outlet port is sealed from the inlet port.
 4. The flow control device according to claim 2, wherein when the sealing member is in a second configuration, the sealing area is in sealing engagement with the second seat such that the inlet port is fluidly communicable with the first outlet port and the second outlet port is sealed from the inlet port.
 5. The flow control device according to claim 2, wherein when the sealing member is in a third configuration, the sealing area is disposed between the first and second seats such that the inlet port is in fluid communication with the first outlet port and the second outlet port.
 6. The flow control device according to claim 1, wherein the sealing member includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.
 7. The flow control device according to claim 1, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.
 8. The flow control device according to claim 1, wherein the first and second seats are annular and the sealing member is annular.
 9. The flow control device according to claim 1, wherein the actuator is a stepper motor and the sealing member is a spool.
 10. A transport refrigeration system, comprising: a refrigeration circuit, including: a compressor, a flow control device, a condenser, and an evaporator fluidly connected, wherein the flow control device includes: an inlet port fluidly connected to a discharge port of the compressor; first and second outlet ports, wherein: the first outlet port is fluidly connectable to the evaporator, and the second outlet port is fluidly connectable to the condenser; an actuator; a first seat disposed between the inlet port and the first outlet port; a second seat disposed between the inlet port and the second outlet port; and a single sealing member movable by the actuator, the sealing member configured to be sealingly engageable with the first and second seats.
 11. The transport refrigeration system according to claim 10, wherein the actuator is a stepper motor and the sealing member is a spool.
 12. The transport refrigeration system according to claim 10, wherein a location of the sealing member corresponds to an operating mode of the transport refrigeration system.
 13. The transport refrigeration system according to claim 10, wherein in a heating/defrost mode, the flow control device is configured to direct fluid flow from the first outlet port.
 14. The transport refrigeration system according to claim 10, wherein in a cooling mode, the flow control device is configured to direct fluid flow from the second outlet port.
 15. The transport refrigeration system according to claim 10, wherein in a modulating mode, the flow control device is configured to direct a portion of fluid flow from the first outlet and a portion of the fluid flow from the second outlet.
 16. The transport refrigeration system according to claim 10, wherein the sealing member includes a longitudinal axis and the inlet port is on a first side of the longitudinal axis and the first and second outlet ports are on a second side of the longitudinal axis.
 17. The transport refrigeration system according to claim 10, wherein the inlet port includes an inlet longitudinal axis, and the first and second outlet ports include first and second outlet longitudinal axes, the first outlet longitudinal axis being disposed on a first side of the inlet longitudinal axis and the second outlet longitudinal axis being disposed on a second side of the inlet longitudinal axis.
 18. The transport refrigeration system according to claim 10, wherein the first and second seats are annular and the sealing member is annular.
 19. A method for controlling an operating mode of a refrigeration circuit, the refrigeration circuit including a compressor, a flow control device, a condenser, and an evaporator fluidly connected, wherein the flow control device includes an inlet port fluidly connected to a discharge port of the compressor, first and second outlet ports, the first outlet port being fluidly connectable to the evaporator, and the second outlet port being fluidly connectable to the condenser, a stepper motor, a first seat disposed between the inlet port and the first outlet port, a second seat disposed between the inlet port and the second outlet port, and a single spool movable by the stepper motor, the spool configured to be sealingly engageable with the first and second seats, the method comprising: receiving a heat transfer fluid from the compressor at the inlet port of the flow control device; and translating the single spool between the first and second seats to direct the heat transfer fluid to one of the first and second outlet ports, wherein: in a cooling mode, translating the single spool to be sealingly engaged with the first seat such that heat transfer fluid is directed to the second outlet port, and in a heating/defrost mode, translating the single spool to be sealingly engaged with the second seat such that the heat transfer fluid is directed to the first outlet port.
 20. The method according to claim 19, wherein in a modulating mode, translating the single spool to an intermediate location between the first and second seats for directing a portion of the heat transfer fluid to the first outlet port and for directing another portion of the heat transfer fluid to the second outlet port. 